Multipolar Lattice Resonances in Plasmonic Finite-Size Metasurfaces

Collective lattice resonances in regular arrays of plasmonic nanoparticles have attracted much attention due to a large number of applications in optics and photonics. Most of the research in this field is concentrated on the electric dipolar lattice resonances, leaving higher-order multipolar lattice resonances in plasmonic nanostructures relatively unexplored. Just a few works report exceptionally high-Q multipolar lattice resonances in plasmonic arrays, but only with infinite extent (i.e., perfectly periodic). In this work, we comprehensively study multipolar collective lattice resonances both in finite and in infinite arrays of Au and Al plasmonic nanoparticles using a rigorous theoretical treatment. It is shown that multipolar lattice resonances in the relatively large (up to 6400 nanoparticles) finite arrays exhibit broader full width at half maximum (FWHM) compared to similar resonances in the infinite arrays. We argue that our results are of particular importance for the practical implementation of multipolar lattice resonances in different photonics applications.

Automated summary

This study comprehensively investigates the multipolar collective lattice resonances in finite and infinite arrays of gold and aluminum plasmonic nanoparticles. The results show that the multipolar lattice resonances in relatively large finite arrays exhibit broader full width at half maximum (FWHM) compared to similar resonances in infinite arrays. Our findings are important for the practical implementation of multipolar lattice resonances in various photonics applications.